Friday, September 18

What is nevus comedonicus?

Nevus comedonicus (comedo nevus) is a rare hamartoma of the pilosebaceous unit. It is considered as an abnormal differentiation and development of follicular structures.

The failure of the folliculosebaceous unit to develop properly, results in its inability to form hair or sebaceous glands. Only keratin is produced which accumulates in the dilated pores as comedo-like keratinous plugs.
In 1895, Kofmann described the first case of this rare skin abnormality and used the term "comedo nevus".

Clinical Characteristics

Nevus comedonicus (NC) is a rare type of epidermal nevus, characterized by dilated follicular ostia (openings) with comedo-like keratinous plugs. The comedo-like lesions are closely arranged in a honeycomb pattern. Though these lesions are asymptomatic with acne-like characteristics, in some cases there may be inflammation and formation of suppurative cysts, papules, pustules and abscesses. The lesions tend to grow more quickly at puberty.

Nevus comedonicus lesions present, unilateral, bilateral, linear, plaque-like, interrupted, zosteriform, segmental or Blaschko linear pattern of distribution. The intervening skin may appear normal or show hypertrophy and hyperkeratosis. These comedo-like cysts have a predilection for the face and neck region. In rare cases they may affect other parts of the body, including scalp, genitalia, trunk, limbs, palms and soles.

Who can get nevus comedonicus?

These comedo lesions develops shortly after birth and in most of the patients they tend to occur before the age of ten years. In rare cases adults may also develop these comedo-like lesions. There is no gender or racial predilection. The presence of NC in several families has been documented. The occurrence of nevus comedonicus in homozygous twins has been reported. The prevalence of this disorder has been estimated to be 1 in 45,000 to 100,000 individuals.

What causes nevus comedonicus?

These lesions are considered as hamartoma caused by abnormal differentiation and development of follicular structures. The exact etiology of these comedo lesions is unclear. As nevus comedonicus can occur congenitally a genetic mosaicism has been proposed. However, the cause of its occurrence late in life is not known. Though generally considered as a failure of folliculosebaceous unit to develop properly, the presence of comedo nevus in a palm or sole indicates the sweat duct dilatation with keratin plugs in the opening.

Diagnosis of comedo nevus

Diagnosis of nevus comedonicus may be made by physical examination and dermoscopy. A magnetic resonance imaging review may help in the diagnosis of nevus comedonicus. Skin biopsy may also help to confirm the diagnosis. Histologic studies of comedo cysts will reveal absence of sebaceous glands or their rudimentary presence. The hair follicles will appear underdeveloped and devoid of hair shafts. Nevus comedonicus has to be differentiated from similar-looking ailments like acne vulgaris, familial dyskeratotic comedones, lichen striatus and keratosis pilaris.

Complications

These comedonicus lesions may develop into multiple masses with typical cysts containing keratinized tissue. Inflammatory form of comedo nevus may lead to formation of suppurative cysts, papules, pustules and abscesses with repeated bacterial infections and drainage. Such comedo lesions can cause formation of scar tissue.

Nevus comedonicus treatment

Conservative treatments
Conservative treatment options include application of emollients, moisturizers and keratolytics. Salicylic acid, or 12% ammonium lactate solution may be applied to dissolve the keratinous plugs and improve the cosmetic appearance. Superficial shaving, comedo extraction, or dermabrasion are some of the treatment methods giving mixed results and the recurrence of comedo-like lesion is very common.

Inflamed comedo nevus may require application of topical corticosteroids. Limited results were achieved with the topical application of anti-comedo retinoid agents like topical tretinoin and tazarotene. Oral retinoids like isotretinoin were found to be ineffective in most cases of comedo-like lesions. Complete resolution of NC can not be achieved by treatment with topical or oral retinoids and relapses are common.

Surgical procedures
Localized comedo-like lesions can be surgically removed with successful results. Radical resection may be necessary to remove large, multiple comedo cysts and prevent their further invagination. Long linear lesions, especially on limbs, removed by surgical excision require complex decongestive treatment to support and enhance healing process. Large and extensive comedo lesions will require skin transplants for defect closure.

These lesions are common in children. They are well-circumscribed and have even increase in the melanin pigment deposit.

The café au lait spots appear in infancy and may not be discernible. They may be observed with Wood lamp as faint lesions. As the child grows, they may enlarge in size, darken and become obvious by the age of two years. These skin lesions, as such are harmless, but are more frequently observed in patients with certain genetic and systemic diseases.

The café au lait macules occur with greater frequency in populations of Hispanic and African origins. There is no gender predilection and these skin hyperpigmentation spots can be seen in all age groups. The size and number of these skin lesions vary widely among individuals. The presence of six or more café au lait spots larger than 5 mm in diameter in children should raise the suspicion of a genetic or systemic disorder.

Café au lait macules causes

Café au lait spots are caused by an increase in melanin deposits in the epidermal cells of the lesion area. These lesions may arise from diverse and unrelated causes. In patients with neurofibromatosis type 1 (NF1), there is significant increase in the melanocyte density. The café au lait lesions associated with genetic and systemic disorders are caused by, inheritance, mutations in specific genes and spontaneous mutations.

Syndromes associated with café au lait spots

The presence of café au lait macules is one of the symptoms of genetic and systemic diseases such as neurofibromatosis type 1 (NF1), McCune-Albright syndrome, tuberous sclerosis, and Fanconi anemia.

Neurofibromatosis type 1 (NF1)

Neurofibromatosis type 1 (NF1) is the most common type of neurofibromatosis, affecting about 1 in 3,000 newborns. Café au lait spots are usually the earliest manifestations of NF1. These macules are observed in nearly 95% of patients with NF1. The presence of six or more café au lait macules larger than 5 mm in diameter and also freckling in the axillary or inguinal regions is one of the diagnostic criteria for NF1. NF1 causes tumors along the nervous system with symptoms such as multiple small cutaneous neurofibromas, optic gliomas, vision disorders, cognitive problems and epilepsy. It is an inherited disorder caused by mutation in the NF1 gene located on chromosome number 17.

Café au lait spots

Neurofibromatosis type 2 (NF2)

Neurofibromatosis type 2 (NF2) is a rare type of neurofibromatosis, affecting 1 in 33,000 individuals. Patients with NF2 have mutation in NF2 gene located on chromosome number 22. They develops tumours on the nerves responsible for hearing and balance. They will have gradual hearing loss, that usually gets worse over time. They may also have café au lait macules.

Legius syndrome

Legius syndrome (LS) is an autosomal dominant genetic disorder. Nearly all LS patients have café au lait macules. LS is often mistaken for neurofibromatosis type I. It is caused by mutations in the SPRED1 gene. Other skin manifestations are, hyperpigmentation spots in the armpits and/or groin. The patient may suffers from lipomas, macrocephaly, ADHD, delayed development and cognitive problems.

McCune-Albright syndrome

McCune–Albright syndrome is a genetic disorder of bones, skin pigmentation and hormonal problems. McCune-Albright syndrome is caused by mutations in the GNAS1 gene. The condition is characterized by bone fractures, deformity of the legs, arms and skull, gigantism, large café au lait macules, hyperpigmentation spots on the skin and early puberty.

Bloom–Torre–Machacek syndrome

Bloom syndrome is a rare autosomal recessive disorder with several debilitating manifestations and shortened life expectancy. Bloom syndrome is also characterized by skin manifestations like skin sensitivity to light, skin rash, pigmentation changes, telangiectasias and café au lait spots. Persons with Bloom syndrome are predisposed to develop cancers due to genome instability and immunodeficiency.

Café au lait macules symptoms

These lesions have the typical color of milk added coffee. The Café au lait spots vary in size, appearing as small freckles to large macules. The CAL spots, not associated with any neurocutaneous disorders or genetic abnormalities, usually appear as large, solitary, light brown to brown macules. Freckling in the axillary or inguinal regions and the presence of six or more café au lait macules larger than 5 mm in diameter are symptoms of NF1.

Café au lait macules diagnosis

In infants, if café au lait spots are suspected, Wood lamp is a handy tool for finding the faint marks. Current guidelines support evaluation of children with multiple macules for genetic disorders, especially NF1. The macules associated with genetic syndromes require genetic testing and counseling. The CAL lesions may have to be differentiated from melanocytic nevi, Becker's nevus, nevus spilus and nevus simplex.

Café au lait macules treatment

Café au lait spots without any association to systemic disorders, need no treatment. If the lesions are of cosmetic concern, they can be removed with lasers. Laser therapy with lasers such as PDL, Er:YAG, QS Nd:YAG, has given varying degree of success. In some cases of café au lait lesions complete clearance was achieved whereas in some cases there was recurrence or postinflammatory hyperpigmentation. The size of the macule, its location and the presence of associated disorder, if any, will help in selecting the best course of treatment for cafe au Lait spots.

It was first described in 1867 by Erasmus Wilson, an English physician. It is present in nearly 10 to 15% of healthy adults and children. The term "Araneus" denotes a genus of orb-weaving spiders.

Nevus araneus occurs as a result of the dilation of the preexisting blood vessels. Araneus lesion consists of a central ascending arteriole from which numerous small vessels radiate. The central arteriole resembles a spider's body and the radiating vessels appear like spider legs. These lesions range in size from being just visible to 10mm in diameter.

Vascular spider lesions are commonly found in the distribution of the superior vena cava, occurring on the face, below the eyes, over the cheekbones, neck, upper trunk and arms. The nevus araneus association to the superior vena cava is disputed by some researchers. Children may have them also on their fingers and hands. Vascular spider is more common in women than in men, probably due to pregnancy and oral contraceptive use related occurrences.

Pathophysiology and causes

The dilation of the preexisting dermal blood vessels is the primary cause of the appearance of these nevus araneus lesions. The vascular dilation is mostly idiopathic and is caused by the failure of the sphincteric muscle surrounding an arteriole. Compressing the central arteriole with a pinhead causes temporary obliteration of the telangiectasia. Releasing the pressure causes rush of blood from the central arteriole to the branching dilated blood vessels. Occasionally the arteriole may be observed to pulsate. Punctured arteriole may bleed profusely.

Araneus vascular malformations are normally unrelated to systemic diseases and health conditions. However, in a few cases, they have been associated with hyperthyroidism and thyrotoxicosis. High levels of circulating estrogen is another cause of araneus lesions, as in the case of pregnancy or during the use of oral contraceptives. The condition resolves in a few months after giving birth or after stopping oral contraceptive pills.

Nevus araneus is also associated with liver ailments such as chronic liver disease, hepatic failure, liver cirrhosis, hepatopulmonary syndrome and hepatic fibrosis. The appearance of numerous, large lesions in atypical locations is one of the strong clinical pointers to liver disease and alcohol abuse related severe liver dysfunction.

Vedamurthy M. et al. reported a case of a 36 year-old, non-alcoholic man with multiple, erythematous, asymptomatic macules distributed mainly on the chest. Earlier, the condition was diagnosed as an allergic reaction and antihistamines were prescribed. Six months later, the patient developed jaundice and diagnosed to have chronic liver disease. Dermatological examination revealed the presence of numerous spider nevi on the chest and abdomen. The researchers concluded that, "it would be advisable to screen the patients with spider nevi for liver disease as early detection could prove to be beneficial to the patient".

These nevus araneus lesions are probably due to the diseased liver being unable to optimally metabolize circulating estrogens. The elevated levels of estradiol/free testosterone ratio, serum vascular growth factors and substance P are other causes attributed to cause these lesions.

Nevus araneus symptoms

Nevus araneus appears like a spider, with a central, small, red papule surrounded by several radiating blood vessels. Pressure on the lesion causes temporary obliteration. When the pressure is removed, the lesion refills from the center to the radiating vessels. Occasionally the central arteriole is observed to pulsate. Normally, vascular spider appears on the upper half of the body.

Spider nevus diagnosis

Diagnosis of vascular spider is usually by clinical observation and by observing the classic refill pattern from the central arteriole to the radiating blood vessels. Blanching and temporary obliteration of the nevus araneus lesion on pressure is another indicator. Araneus malformations may have to be differentiated from telangiectatic mats (lacking central arteriole), varicose Veins, hemangioma, Campbell de Morgan spots, Osler-Rendu-Weber syndrome, telangiectasia with different etiologies and insect bites.

Nevus araneus treatment

For benign, idiopathic, nevus araneus, treatment usually is not necessary. Some lesions resolve rapidly while some may regress over the course of several years. Some vascular lesions may be permanent. In pregnant women, the vascular malformations caused by circulating hormones may resolve in a few months after childbirth. Those on oral contraceptives or hormonal supplementation may find spider nevus resolution after discontinuing the medications. Liver disease connected lesions may regress upon treatment of the ailment or after liver transplantation.

NLCS was first reported by Hoffman and Zurhelle in 1921. This uncommon hamartomatous nevus manifests as soft papules appearing on the buttock, thigh or abdomen.

The nevus lipomatosus superficialis is commonly present at birth, can appear later in life. It is classified into classical and solitary forms. The classical form is characterized by clusters of pedunculated, flesh-colored or yellowish papules, nodules, or plaques which may have a smooth, wrinkled or cerebriform surface. The other very rare form of NLCS manifests as a solitary dome-shaped or sessile papule.

The nevus lipomatosus cutaneous superficialis lesions are usually unilateral and may appear in linear or zosteriform cutaneous distribution. Multiple papules of various sizes may appear simultaneously.

They are usually static and in some cases they may progress slowly over years. Normally, NLCS papules do not recur after surgical removal. They are painless and do not discharge. These lesions are not hereditary.

Some rare coexistent anomalies

Ashish Dhamija et al. reported a rare case of classical NLCS in a 26-year-old man with bilateral cerebriform nodules over the perianal area. The patient reported occasional foul-smelling discharge from the nodules. The surface of the lesion had multiple open comedones. The patient also informed that the lesions also occurred 5 years earlier and were surgically removed. Brasanac and Boricic reported a case in which the lesion also contained dermoid cysts.

Nevus lipomatosus superficialis causes

NLCS is a rare benign idiopathic hamartomatous condition. It is an ectopic presence of mature adipose tissue in the dermis layer of skin. The epidermis is usually normal. The reticular dermis has pockets of mature adipocytes. Nevus lipomatosus cutaneous superficialis with a 2p24 gene deletion has been recently reported.

not associated with skin disorders, systemic abnormalities or malignant transformation.

Nevus lipomatosus superficialis diagnosis

A general physical examination of these cutaneous lesion will present multiple, skin-colored, pedunculated, cerebriform, soft, asymptomatic nodules of varying sizes. Skin biopsy microscopy will show the presence of clusters of mature adipose tissue in the dermis, mostly around the perivascular area, interposed among the collagen bundles.

Solitary nevus lipomatosus cutaneous superficialis may require to be differentiated from fibrolipoma, as histologically it appears similar to fibrolipoma. The differential diagnosis has to include, fibrolipoma, neurofibromatosis, nevus sebaceous, lymphangioma, neurofibroma and fibroepithelial polyp.

Nevus lipomatosus cutaneous superficialis treatment

Treatment is usually not necessary for NLCS. If there is cosmetic concern or if it is coming in the way of daily activities, surgical excision is done. Cryotherapy yields mixed results. There is a report of a case of successfully treated classic NLCS with CO2 laser. After surgery, recurrence of nevus lipomatosus cutaneous superficialis is very rare.

Paronychia signs and symptoms

Pus may develop along the nail margin. In severe acute conditions pus is also formed below the nail plate.

In case of chronic condition the cuticle and proximal nail fold may get retracted and separated from the nail plate. The paronychia infection may spread into deeper tissues of pulp space in the palm side of the finger causing felon which requires aggressive treatment. Severe acute infection can cause chills and fever.

In patients with acute form of paronychia, typically only one nail is involved. In chronic form, usually the thumb and second or third fingers of the dominant hand are involved. The diagnosis is usually by visual observations. Chronic or acute conditions not responding to treatment may require differential diagnosis to rule out squamous cell carcinoma, malignant tumors, eczema and psoriasis.

Herpetic whitlow must be ruled out as the treatments are drastically different and mistreatment may do more harm than good.

Paronychia treatment

Nail fold infection, especially the chronic form, is prevalent in laundry workers, agricultural laborers, food handlers, dishwashers, fishermen, fishmongers, fish farm workers, dairy workers, watersports personals and swimmers. Treatment of paronychia is determined by the degree of inflammation and infection and also whether it is acute or chronic.

Warm water soak treatment for paronychia

Mild, acute cases of paronychia without abscess only require soaking the affected finger or toe in warm water to which antibacterial soap/epsom salt/vinegar is added. At a time about 15-20 minutes of soaking is required and it may be repeated four or five times a day. The warm water increases the circulation to the soaked area, inducing the immune cells to do their job of clearing the infection. The added ingredients will function as mild antibiotic.

Topical applications

Chronic paronychia treatment is typically different from acute treatment.For acute nail fold infection where there appears to be only cellulitis, topical application of antibacterial preparations may be applied apart from warm water soaking to totally remove the infection. If chronic infection with cellulitis is seen antifungal preparations and also steroids may be applied. A combination of antifungal and steroid had been found to be very effective.

Oral antibiotics

Acute paronychia with abscess and pus formation requires apart from draining the pus, use of oral antibacterial like clindamycin, cefadroxil or amoxicillin to clear the infection. Chronic fungal paronychia may require a long course of systemic antifungal medication. There is always a possibility a concurrent bacterial infection requiring the use of antibacterial medication.

Paronychia of finger

Surgical intervention in paronychia

Abscess formation and pus collection in acute paronychia requires surgical intervention to drain the pus. This may be done in several different ways. Normally the cuticle at the abscess is raised making passage for the pus to drain out. If neglected, acute or chronic condition may worsen affecting the deeper tissues it may cause ascending lymphangitis or sepsis.

In cases of paronychia where the abscess is further away from the cuticle, a small incision can be made directly over the abscess to drain the pus followed by eponychial marsupialization. The procedure is usually pain free and in exceptional cases local anesthetic can be used. The wound may be packed for two days with a piece of plain gauze packing soaked in antibiotic cream. After removal of the packing, the patient may be advised warm water soak treatment till the acute reddening and inflammation subsides.

In chronic paronychia where the nail plate and nail bed are damaged partial or total removal of the nail become necessary. This procedure is usually done under local anesthesia and the wound will take several days to heal. The patient should also try to find and avoid the root cause of the chronic condition whenever possible, or chronic paronychia may recur.

Thursday, July 23

Home › What is ingrown hair › Ingrown hair causes and symptomsWhat is ingrown hair?
Ingrown hair occurs when the sharp, cut-end of thick hair grows sideways, at an abnormal angle, penetrating into the dermal skin.

Quite often the condition resolves by itself without any clinical symptoms. In some persons ingrown hair may cause small pimple-like bumps with symptoms like reddening, inflammation, pain and pus formation. Though in most of the cases, the ingrowth involves the skin areas which are shaved, tweezed or waxed, it can occur in any hairy part on the body.

Ingrown hair causes

Shaving, tweezing or waxing are the primary causes of these ingrowths.

Coarse or tightly curling thick hairs are the predisposing factors, as the cut end is more likely to bend back and grow into the skin leading to an inflammatory reaction.

Individuals with higher levels of circulating androgenic hormones have excessive growth of thick hair and are prone to these ingrowths.

Shaving very close to the skin can cut the hair strand deep inside the follicle and increase the risk of ingrowth.

Shaving against the direction of growth causes the strands to get pulled and cut close to their root, increasing the risk of ingrowth.

Friction from tight clothing, may precipitate the situation.

Blocking of the follicle with dead skin debris may cause the strands to grow sideways.

Certain genetic factors may predispose a person and cause these bumps in the beard area.

Pseudofolliculitis barbae

Pseudofolliculitis barbae, a type of extensive ingrowth, occurs in persons with thick, coarse hair. It is a common chronic inflammatory disorder in men of African ancestry, occurring most often in regions of thick hair growth after shaving. The condition causes erythematous papules with symptoms of pain and pus formation. A common polymorphism in a keratin gene (K6hf) may be a genetic risk factor for pseudofolliculitis barbae type of ingrowth.

Ingrown hair symptoms

In most of the conditions, the symptoms may be limited to small reddish bumps. The symptoms like rash, tenderness and itching skin may also appear. Infected ingrowth may present symptoms such as pimple like inflammation, raised large bumps, abscesses and pruritic erythematous pustules. Certain other medical conditions like folliculitis, keratosis pilaris and furuncle may mimic the symptoms and are to differentially diagnosed.

Ingrown hair

Common signs and symptoms include:

inflammation,

papules,

pustules,

hyperpigmentation,

rash,

pain,

pruritus and

embedded hairs in the site.

Ingrown hair treatment

Avoiding shaving for two to three weeks may causes the existing bumps to resolve. Extrafollicular ingrowths can usually be tweezed gently and cut above the skin level. Transfollicular ingrowths as well as ingrowths with symptoms of pus and severe inflammation may require medical treatment. Chemical depilatories, topical creams, laser therapy or surgical removal are the other treatment options available.

Ingrown hair prevention

The best way to prevent the ingrowth is to refrain from shaving or using a beard trimmer. If shaving is necessary, wetting the skin with warm water and using a shaving gel may prevent the hair strand from getting pulled and getting cut close to the root. Avoiding shaving close to skin will enable the cut ends to grow out of the follicle smoothly. Shaving against the direction of the growth of strand must be avoided to prevent ingrown hair.